NEW YORK - One-third of women and 18% of men with COVID-19 and ST-segment elevation myocardial infarction (STEMI) have no culprit lesion detectable on angiography, according to new data from the North American COVID-19 Myocardial Infarction (NACMI) registry.

This is a "startling" finding, say the researchers, considering that rates of MI with non-obstructive coronary arteries (MINOCA) usually makes up only 3.5% to 6.5% of these types of heart attacks in the absence of COVID-19 infection.

There is a "lack of research and clear guidance on how to treat STEMI patients without an identified culprit lesion, many of which are women," Dr. Odayme Quesada, with The Christ Hospital Women's Heart Center in Cincinnati, Ohio, said in a news release.

He presented the results at Society for Cardiovascular Angiography and Interventions (SCAI) annual meeting, with simultaneous publication in JSCAI.

Using the NACMI registry, the researchers compared clinical characteristics, management strategies and outcomes of 585 patients with STEMI and COVID-19 (26% women).

Compared with men, women were significantly older, had higher rates of diabetes and stroke or transient ischemic attack (TIA) and statin use on admission.

Men were more likely to present with chest pain whereas women presented with dyspnea.

Use of primary percutaneous coronary intervention (PCI) was significantly more common in men, whereas medical therapy was used more often in women.

Rates of in-hospital mortality were high and not significantly different in men and women.

"Prior to COVID-19, mortality rates for STEMI had significantly improved in the past decade, with rates as low as 5%. This is in stark contrast to the very poor prognosis observed in our registry of patients with STEMI and COVID-19 infection where in-hospital mortality was 33% for women and 27% for men," they report.

Excess mortality in STEMI associated with COVID-19 could be due to a higher incidence of cardiogenic shock and the presence of pulmonary infiltrates on presentation, suggestive of more severe COVID-19 infection, which carried a two-fold higher risk of in-hospital death in the study.

"The combination of direct effects of the virus, higher risk of thrombotic lesions and microthrombi, delays in patient presentation, deviations from evidence-based STEMI protocol during the early phase of the pandemic resulting in delays, and reduced access to angiography likely contributed to the poor observed prognosis," they add.

They say further research is needed to determine the impact of COVID-19 vaccinations on the incidence and prognosis of STEMI in COVID-19 patients.

"The significant increase in mortality among both men and women in this study highlights the need for continued research to better understand the long-term effects of COVID-19 on cardiovascular health," Dr. Quesada commented in the news release.

"We hope additional analysis of these patient characteristics will help further inform clinicians on best the treatment approach and ultimately improve patient outcomes," he added.

The NACMI registry is a collaborative effort between SCAI, the American College of Cardiology (ACC) and the Canadian Association of Interventional Cardiology.

The registry was established in 2020 to define baseline characteristics and management strategies and outcome data for COVID-19 patients presenting with STEMI. More than 60 medical centers across North America and Canada have contributed data to the registry.

SOURCE: Journal of the Society for Cardiovascular Angiography & Interventions (JSCAI), online May 19, 2022.